Touch panel and liquid crystal display device having the touch panel

ABSTRACT

A touch panel includes plural scanning electrodes, plural detection electrodes that are formed to intersect with the plural scanning electrodes, one or a plurality of layers being disposed between the plural detection electrodes and the plural scanning electrodes, plural holes that are arrayed apart from each other on each of the plural detection electrodes, and shaped into polygons each shaped to have five or more corners in a plan view, and plural dummy electrodes that are formed between the respective adjacent detection electrodes, made of the same material as that of the detection electrode, and electrically isolated from each other, in which the plural dummy electrodes are shaped into the polygons in a plan view.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority from Japanese applicationJP2013-165819 filed on Aug. 9, 2013, the content of which is herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch panel and a display devicehaving the touch panel.

2. Description of the Related Art

In recent years, a touch panel that detects a position which is touchedwith a finger, a dedicated pen or the like has been developed. As thetouch panel of this type, for example, a capacitance type touch sensorhas been known which detects a change in capacitance of a portion thatis subjected to a touch pressing operation (hereinafter referred to as“touch”). In a touch panel of an in-cell touch panel in which commonelectrodes in a liquid crystal display panel of an IPS (In-PlaneSwitching) system are used as scanning electrodes for touch detection,the scanning electrodes, and detection electrodes that intersect withthe scanning electrodes are arranged in a matrix.

JP 2011-248722 A discloses a touch panel having diamond lattice-shapeddetection electrodes in which plural conductor lines lined up inparallel intersect with each other at a given angle. In the touch panelof this type, first electrodes which are the scanning electrodes, andsecond electrodes which are the detection electrodes intersect with eachother at a given angle so that conductor lines forming the firstelectrodes and the second electrodes configure square mesh patterns in aplan view.

SUMMARY OF THE INVENTION

in the touch panel disclosed in JP 2011-248722 A, because the pluralconductor lines are lined up in parallel, side surfaces of the pluralconductor lines reflect light in the same direction due to lightemission from pixels. As a result, the pattern of the detectionelectrodes is visible from an outside of the display device. Also, inthe display device disclosed in JP 2011-248722 A, because the squaremesh patterns are successively adjacent to each other, interferencefringes (hereinafter referred to as “moiré”) in which halftone dots thatare fine patterns successively appear cannot be prevented. This resultsin a risk that the visibility of an image to be displayed through thetouch panel is deteriorated.

The present invention has been made in view of the above circumstances,and therefore aims at preventing the visibility of the image displayedthrough the touch panel from being deteriorated.

(1) According to the present invention, there is provided a touch panel,including: a plurality of scanning electrodes; a plurality of detectionelectrodes that are formed to intersect with the plurality of scanningelectrodes, one or a plurality of layers being disposed between theplurality of detection electrodes and the plurality of scanningelectrodes, a plurality of holes that are arrayed apart from each otheron each of the plurality of detection electrodes, and shaped intopolygons each shaped to have five or more corners in a plan view; and aplurality of dummy electrodes that are formed between the respectiveadjacent detection electrodes, made of the same material as that of thedetection electrode, and electrically isolated from each other, in whichthe plurality of dummy electrodes are shaped into the polygons in a planview.

(2) According to the present invention, in the touch panel according tothe item (1), the plurality of holes shaped into the polygons andarrayed on the detection electrodes, and the plurality of dummyelectrodes may form a uniform contiguous array.

(3) According to the present invention, in the touch panel according tothe item (1) or (2), the planar view shape of the polygons may be viewedas a circle by increasing the number of corners.

(4) According to the present invention, in the touch panel according toany one of the items (1) to (3), in a detection electrode formation areain which the detection electrodes are formed, a ratio of an area of theplurality of holes to an area of the detection. electrodes may be equalto or larger than ⅔ and equal to or smaller than 3/2.

(5) According to the present invention, in the touch panel according toany one of the items (1) to (4), distances between centers of therespective adjacent polygons may be equal to each other.

(6) According to the present invention, the touch panel according to anyone of the items (1) to (5), may further include a shield electrodewhich is an electrode in which the plurality of holes shaped into thepolygons are formed outside of a display area in which the detectionelectrodes are formed.

(7) According to the present invention, there may be provided a liquidcrystal display device, including: the touch panel according to anyoneof the items (1) to (6); pixel electrodes that form an electric fieldwith the scanning electrodes as counter electrodes; and liquid crystalhaving an orientation controlled by the electric field.

(8) Also, according to the present invention, there is provided a touchpanel, including: a plurality of scanning electrodes; a plurality ofdetection electrodes that are formed to intersect with the plurality ofscanning electrodes, one or a plurality of layers being disposed betweenthe plurality of detection electrodes and the plurality of scanningelectrodes, a plurality of holes that are arrayed apart from each otheron each of the detection electrodes, and shaped into polygons eachshaped to have five or more corners in a plan view; and a plurality ofdummy electrodes that are formed between the respective adjacentdetection electrodes, made of the same material as that of the detectionelectrode, and electrically isolated from each other, in which theplurality of dummy electrodes are shaped into polygons each having fiveor more corners in a plan view.

According to the present invention, as compared with the touch panel orthe liquid crystal display device which does not provide the aboveconfigurations, the reflection of light and the generation of moiré onthe polygonal holes in the detection electrodes and the side surfaces ofthe dummy electrodes are suppressed. For that reason, the prevention ofthe visibility of the image displayed through the touch panel from beingdeteriorated can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a liquid crystal displaydevice having a touch panel according to an embodiment of the presentinvention;

FIG. 2 is a schematic cross-sectional view taken along a line II-II ofthe liquid crystal display device illustrated in FIG. 1;

FIG. 3 is a partially enlarged view of an area III of the touch panelillustrated in FIG. 1;

FIG. 4 is a partially enlarged view of an area IV of the touch panelillustrated in FIG. 3;

FIG. 5 is a partially enlarged view illustrating one modification of thetouch panel according to this embodiment in the same viewing field asthat in FIG. 4;

FIG. 6 is a partially enlarged view illustrating another modification ofthe touch panel according to this embodiment in the same viewing fieldas that in FIG. 4;

FIG. 7 is a partially enlarged view illustrating still anothermodification of the touch panel according to this embodiment in the sameviewing field as that in FIG. 4;

FIG. 8 is a partially enlarged view illustrating yet anothermodification of the touch panel according to this embodiment in the sameviewing field as that in FIG. 4;

FIG. 9 is a partially enlarged view illustrating a further modificationof the touch panel according to this embodiment in the same viewingfield as that in FIG. 4;

FIG. 10 is a partially enlarged view illustrating a still furthermodification of the touch panel according to this embodiment in the sameviewing field as that in FIG. 4;

FIG. 11 is a partially enlarged view of an area XI in the touch panelillustrated in FIG. 1; and

FIG. 12 is a partially enlarged view of an area XII in the touch panelillustrated in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a touch panel and a display device according to thisembodiment will be described with the example of a liquid crystaldisplay device 1 with reference to the accompanying drawings. Forfacilitation of understanding the characteristics, the drawings referredto in the following description may illustrate characteristic portionsin an enlarged manner for convenience, and size ratios of the respectivecomponents are not always identical with actual size ratios. Also,materials and the like exemplified the following description areexemplary, and the respective components may be made of materialsdifferent from the exemplary materials, and can be changed withoutdeparture from the spirit thereof.

FIG. is an exploded perspective view of the liquid crystal displaydevice 1 having a touch panel according to an embodiment of the presentinvention. As illustrated in FIG. 1, the liquid crystal display device 1includes a liquid crystal display panel 33, and a front panel 46 havinga display area D and a non-display area E. For convenience ofdescription, a partial configuration of the liquid crystal displaydevice is omitted from FIG. 1.

The liquid crystal display panel 33 is, for example, a liquid crystaldisplay panel of an IPS (In-Plane Switching) system, and includes afirst substrate 10 and a touch panel 42. An area corresponding to thenon-display area E on an upper surface 10 a of the first substrate 10 isconnected with a first flexible circuit board 2 a, and also providedwith a driver IC (integrated circuit) 3. The driver IC 3 is arranged onan upper side of the first substrate 10 for receiving image data from anexternal of the liquid crystal display device 1 through the firstflexible circuit board 2 a. The driver IC 3 receives image data, andsupplies a voltage signal to be applied to scanning electrodes (counterelectrodes) 30 and pixel electrodes 34 to be described later throughcommon wiring 58 for respective pixels.

The touch panel 42 includes the plural scanning electrodes 30, a secondsubstrate 12, and plural detection electrodes 38. The scanningelectrodes 30 are disposed to extend at intervals from each other in adirection X in an area corresponding to the display area D on the uppersurface 10 a of the first substrate 10. Also, the plural scanningelectrodes 30 and the plural detection electrodes 38 extend to intersectwith each other through one or a plurality of layers.

The second substrate 12 is arranged over an upper side of the firstsubstrate 10. In an area corresponding to the display area D on an uppersurface 12 a of the second substrate 12, for example, the pluraldetection electrodes 38 extending in a direction Y are disposed atintervals from each other. The direction Y has only to intersect with adirection X, but it is preferable that the direction Y is orthogonal tothe direction X.

Respective ends of the plural detection electrodes 38 formed in the areacorresponding to the display area D in the direction Y are connected toterminals 40, and an end of the detection electrode 38 formed in thearea corresponding to the non-display area E in the direction Y isconnected to a shield terminal 41. Also, dummy electrodes 39 are formedbetween the respective adjacent detection electrodes 38. The detailedconfigurations of the detection electrodes 38 and the dummy electrodes39 will be described later.

The area corresponding to the non-display area E on the upper surface 12a of the second substrate 12 is connected with a second flexible circuitboard 2 b. The second flexible circuit board 2 b is disposed forelectric connection between the detection electrodes 38 and an externaldevice, and a part of the second flexible circuit board 2 b is connectedto the first flexible circuit board 2 a.

The front panel 46 is arranged on an upper side of the second substrate12. The front panel 46 is a member for protecting the liquid crystaldisplay panel 33. The display area D of the front panel 46 has atranslucency, and a lower surface of the non-display area E is coveredwith a black matrix BM.

Subsequently, a configuration of the display area D in the liquidcrystal display device 1 will be described in detail. FIG. 2 is aschematic cross-sectional view taken along a line II-II of the liquidcrystal display device 1 illustrated in FIG. 1.

The first substrate 10 is an insulating substrate made of, for example,glass, and a circuit layer 11, the scanning electrodes 30, and the pixelelectrodes 34 are formed on the upper surface 10 a of the firstsubstrate 10 in the stated order.

The circuit layer 11 is a layer on which thin film transistors 18, afirst insulating film (gate insulating film) 22, and electric wiring notshown are formed, and disposed to drive the pixel electrodes 34. Thethin film transistors 18 are disposed on the first substrate 10 forrespective pixels P. Each of the thin film transistors 18 includes, forexample, a polysilicon semiconductor layer 20, the first insulating film22, a gate electrode 24, a second insulating film 25, a source electrode26, and a drain electrode 28.

An upper side of the than film transistor 18 is covered with a thirdinsulating film (flattening film) 29. The flattening film 29 is a layermade of an insulating material, and formed between the first substrate10 and the pixel electrodes 34, to thereby electrically isolate betweenthe adjacent thin film transistors 18 or between the thin filmtransistors 18 and the pixel electrodes 34.

The scanning electrodes 30 are formed over the flattening film 29, andthe pixel electrodes 34 are formed over upper sides of the scanningelectrodes 30 through a fourth insulating film 32. The el electrodes 34are electrodes formed for the respective pixels for the purpose ofdriving liquid crystal 36 which will be described later. In thisembodiment, the pixel electrodes 34 are located closer to the secondsubstrate 12 side than the scanning electrodes 30. However, thepositional relationship may be reversed. The pixel electrodes 34 areconnected to the thin film transistor 18 through contact holes 34 a.

The second substrate 12 is arranged over the pixel electrodes 34 througha first oriented film 35 a, the liquid crystal 36, and a second orientedfilm 35 b. With the above configuration, the pixel electrodes 34 eachform an electric field in cooperation with the corresponding scanningelectrode 30 as the counter electrode. An orientation of the liquidcrystal 36 is controlled by an electric field generated between thescanning electrodes 30 and the pixel electrodes 34.

The second substrate 12 is, for example, a color filter substrate, andhas a color filter or a black matrix not shown formed thereon. Thedetection electrodes 38 and the dummy electrodes 39 that will bedescribed later are formed over the second substrate 12, and the frontpanel 46 is stuck on the detection electrodes 38 and the dummyelectrodes 39 through an adhesion layer 44.

Hereinafter, a configuration of the detection electrodes 38 and thedummy electrodes 39 will be described in detail. FIG. 3 is a partiallyenlarged view of an area III of the touch panel 42 illustrated inFIG. 1. For convenience of description, illustrations other than thedetection electrodes 38 and the dummy electrodes 39 are omitted in FIG.3. The detection electrodes 38 are electrodes for detecting whether thefront panel 46 is touched from the external, or not based on thedifference of capacitance between the detection electrodes 38 and thescanning electrodes 30.

If areas in which the detection electrodes 38 are formed are detectionelectrode formation areas 138, the detection electrodes (the detectionelectrode formation areas 138) extend in the direction Y, and the pluraldetection electrodes 38 adjacent to each other in the direction X arealigned at intervals from each other. Also, the detection electrodes 38are made of, for example, a translucent conductive material such as ITO(indium tin oxide).

The plural dummy electrodes 39 are electrodes which are formed betweenthe respective adjacent detection electrodes 38, made of the samematerial of the detection electrodes 38, and electrically isolated fromeach other. When an area in which the plural dummy electrodes are formedbetween the respective detection electrodes 38 is a dummy electrodeformation area 139, the dummy electrode formation area 139 extends inthe direction Y, and fills a space between the respective adjacentdetection electrodes 38.

FIG. 4 is a partially enlarged view of an area IV of the touch panel 42illustrated in FIG. 3. For convenience of description, illustrationsother than the detection electrodes 38, the dummy electrodes 39, and thepixels P are omitted in FIG. 4. As lustrated in FIG. 4, in the detectionelectrodes 38, plural pentagonal holes 38 b each shaped to have fivecorners 38 a in a plan view are arrayed at intervals from each other.The respective holes 38 b are arrayed at given intervals and pitches ina zigzag pattern, and arrayed regularly so that distances between acenter of one hole 38 b and respective centers of six holes 38 badjacent to one hole 38 b are identical with each other. The number ofcorners 38 a has only to be five or more, and the holes 38 b are eachformed into a polygonal shape having five or more corners 38 a in a planview. With the above configuration, at least a part of respective sides38 c of the holes 38 b is not arrayed in parallel to an outer peripheryP₁ of the pixel P which is formed into a rectangular shape in a planview, and extends in a direction intersecting with the outer peripheryP₁.

The respective shapes of the plural dummy electrodes 39 formed in thedummy electrode formation area 139 have the same polygonal shape as thatof the holes 38 b in the detection electrodes 38. Specifically, thedummy electrodes 39 each have five corners 39 b and five sides 39 c aswith the holes 38 b. The “same polygonal shape” in this embodimentincludes not only the completely identical polygonal shape, but also ashape deviated from the identical shape within the margin of error dueto a manufacturing process.

As compared with the touch panel or the liquid crystal display devicehaving the detection electrodes in which rectangular holes or groovedholes are formed, in the touch panel 42 and the liquid crystal displaydevice 1 configured as described above in this embodiment, therespective sides 38 c of the holes 38 b of the detection electrodes 38and the outer periphery P₁ of the pixels P, and the respective sides 39c of the dummy electrodes 39 and the outer periphery P₁ of the pixels Pare prevented from being arranged in parallel to each other.

For that reason, as compared with the touch panel and the liquid crystaldisplay device with no provision of the above configuration, the lightemission from the pixels P is prevented from being reflected from therespective sides 38 c of the detection electrodes 38 and the respectivesides 39 c of the dummy electrodes 39, and advancing in the samedirection. As a result, the patterns of the detection electrodes 38 andthe dummy electrodes 39 are prevented from being visible from theoutside of the touch panel 42. Also, because the respective sides 38 cof the detection electrodes 38 and the respective sides 39 c of thedummy electrodes 39 are prevented from being successively arranged inparallel to each other, the generation of moiré can be suppressed.

With the above configuration, the touch panel 42 and the liquid crystaldisplay device 1 according to this embodiment can realize the preventionof the visibility of the image displayed through the touch panel 42 frombeing deteriorated.

Also, because the shape of the holes 38 b of the detection electrodes 38are polygonal in the plan view, the light reflected on the side surfacesof the holes 38 b is prevented from being focused on one point. For thatreason, a difference in the visibility between the detection electrodes38 and the dummy electrode formation area 139 is suppressed.

It is preferable that the detection electrodes 38 and the dummyelectrodes 39 are formed through photolithography. When the detectionelectrodes 38 and the dummy electrodes 39 are formed byphotolithography, the pattern becomes higher in definition, and theabove mentioned effects can be further obtained.

It is preferable that a radius d₁ (radius d₁ of the dummy electrodes 39)of the holes 38 b of the detection electrodes 38 is equal to or largerthan 5 μm, and equal to or smaller than 250 μm. When the radius d₁ isequal to or larger than 5 μm, and equal to or smaller than 250 μm, theholes 38 b of the detection electrodes 38 and the dummy electrodes 39are prevented from being viewed, and a precision of the shapes of theholes 38 b and the dummy electrodes 39 in the plan view can be kept.

Also, it is preferable that a distance d₂ (a distance d₂ between therespective adjacent dummy electrodes 39) between holes 38 b of therespective adjacent detection electrodes 38 is formed with a size withina processable range and a size preventing visibility. Specifically, itis preferable that the distance d₂ is equal to or larger than 5 μm, andequal to or smaller than 250 μm. When the distance d₂ is equal to orlarger than 5 μm, and equal to or smaller than 250 μm, the visibility ofthe holes 38 b of the detection electrodes 38 and the dummy electrodes39 can be prevented, and an electric resistance of the detectionelectrodes 38 can be suppressed.

Also, is preferable that the distance d₂ (distance d₂ between therespective adjacent dummy electrodes 39) between the holes 38 b of therespective adjacent detection electrodes 38, and a length L₁ of longsides and a length L₂ of short sides of the pixels P in the plan vieware different from each other. Since the touch panel 42 and the liquidcrystal display device 1 according to this embodiment have the aboveconfiguration, positional relationships between the respective sides 38c of the holes 38 b and the outer periphery P₁ of the pixels P, andbetween the respective sides 39 c of the dummy electrodes 39 and theouter periphery P₁ of the pixels suppress the generation of moiré.

Also, it is prefer that the plural holes 38 b of the detectionelectrodes 38, and the plural dummy electrodes 39 have a uniformcontiguous array. Specifically, if a boundary between the e detectionelectrode formation areas 138 and the dummy electrode formation area 139is a boundary B, shapes S formed by the holes 38 b and the dummyelectrodes 39 adjacent to each other across the boundary B have the samepolygonal shape as that of the holes 38 b and the dummy electrodes 39 inthe plan view. Specifically, on the boundary B, a shape of eachdetection electrode 38 corresponding to a part (specifically,substantially half thereof) of the hole 38 b, and the dummy electrode 39of a shape corresponding to the remaining part of the hole 38 b arearranged in a complementary manner to arrange a boundary structure(shape S).

With the above configuration, the polygonal shapes in the plan viewwhich are configured by the holes 38 b and the dummy electrodes 39, arecontiguously and uniformly arrayed from the detection electrodeformation areas 138 to the dummy electrode formation area 139 (Theshapes S, the holes 38 b, and the dummy electrodes 39 are arrayed atpitches common to each other, and array pitches of the polygonal shapein the plan view are maintained by the shapes S.) With the provision ofthis configuration, as illustrated in FIG. 4, an outer periphery 38 d ofeach detection electrode 38 on the dummy electrode 39 side is notlinear, and a part of the outer periphery 38 d configures the shape S.

Since the touch panel 42 and the liquid crystal display device 1according to this embodiment have the above configuration, light fromthe pixels P is prevented from being reflected in one direction in theouter periphery 38 d of the detection electrodes 38. For that reason,the visibility of the boundary B can be prevented.

Also, it is preferable that an area 38 d ₁ extending from the boundary Btoward each hole 38 b in the outer periphery 38 d is curved. Since thecurved area 38 d ₁ is formed in the outer periphery 38 d, aninterference of light in the outer periphery 38 d is suppressed. Thearea 38 d ₁ can be curved by adjusting a condition of photolithographyand an etching condition in the formation of the detection electrodes 38and the dummy electrodes 39.

Also, it is preferable that a ratio of a total of areas of the pluralholes 38 b (including the part of the plural holes 38 b of the boundarystructure) to an area of the detection electrodes 38 is equal to orlarger than ⅔, and equal to or smaller than 3/2 in the detectionelectrode formation areas 138. Also, it is further desirable that thearea of the detection electrodes 38 in the detection electrode formationarea 138 is set to be equal to or larger than 0.9 times, and equal to orsmaller than 1.1 times of the total area of the holes 38 b formed in thedetection electrodes 38.

To be more specific, the detention electrode formation areas 138 areconfigured by the detection electrodes 38 and the holes 38 b, and if theratio of the total of the areas of the plural holes 38 b to the area ofthe detection electrodes 38 falls within the above range. As a result,the ratio of the area of the detection electrode 38 and the holes 38 bin the detection electrode formation areas 138 falls within a range offrom 3:2 to 2:3.

Also, because the planar shape of the holes 38 b is equal to the planarshape of the dummy electrodes 39, the ratio of the total of the areas ofthe dummy electrodes 39 to the area of the detection electrodes 38 perthe same area is also equal to or larger than ⅔, and equal to or smallerthan 3/2 with the provision of the above configuration.

With the above configuration, an area ratio of the detection electrodes38 and the dummy electrodes 39 within the same area ranges within agiven range from 1:1. As a result, in the touch panel 42 and the liquidcrystal display device 1 according to this embodiment, a difference ofthe visibility is hardly generated as compared with the touch panel andthe liquid crystal display device with no provision above configuration.For that reason, a difference in shading between the detectionelectrodes 38 and the dummy electrode formation area 139 is hardlyvisible, and the prevention of the visibility of the image splayedthrough the touch panel 42 from being deteriorated can be realized.

Also, it is preferable that if distances between centers c₁ of therespective adjacent holes 38 b, and distances between centers c₂ of therespective adjacent dummy electrodes 39 are set to a distance thedistance d₃ in the respective holes 38 b is equal to the distance in therespective dummy electrodes 39.

With the above configuration, the holes 38 b are arranged in eachdetection electrode 38 in a closest manner, and the dummy electrodes 39are arranged in the dummy electrode formation area 139 in the closestmanner. For that reason, in the touch panel 42 and the liquid crystaldisplay device 1 according to this embodiment, the area of the detectionelectrodes 38, and the ratio of the dummy electrodes 39 to the dummyelectrode formation area 139 are easily adjustable, as compared with thetouch panel and the liquid crystal display device with no provision ofthe above configuration. Also, because the distances between therespective adjacent holes 38 b are equal to each other, the electricresistance in the detection electrodes 38 can be suppressed.

Hereinafter, modifications of the touch panel 42 according to thisembodiment will be described. FIG. 5 is a partially enlarged viewillustrating one modification of the touch panel 42 according to thisembodiment in the same viewing field as that in FIG. 4. As illustratedin FIG. 5, the holes 38 b may be each shaped into a hexagon having sixcorners 38 a in a plan view. Likewise, the dummy electrodes 39 may beeach shaped into a hexagon having six corners 39 a. With the aboveconfiguration, at least four sides 38 c of each hole 38 b, and at leastfour sides 39 c of each dummy electrode 39 are not arranged in parallelto the outer periphery P₁ of the pixels P, and extend in directionsintersecting with the outer periphery P₁.

For that reason, the touch panel 42 and the liquid crystal displaydevice 1 according to this embodiment, the respective sides 38 c of theholes 38 b and the outer periphery P₁ of the pixels P, and therespective sides 39 c of the dummy electrodes 39 and the outer peripheryP₁ of the pixels P are prevented from being arranged in parallel to eachother, as compared with the touch panel and the liquid crystal displaydevice with no provision of the above configuration. For that reason,the generation of moiré is suppressed, and the prevention of thevisibility of the image displayed through the touch panel 42 from beingdeteriorated can be realized.

FIG. 6 is a partially enlarged view illustrating another modification ofthe touch panel 42 according to this embodiment in the same viewingfield as that in FIG. 4. As illustrated in FIG. 6, the holes 38 b andthe dummy electrodes 39 may be shaped into heptagons having sevencorners 38 a and 39 a, respectively. Since the holes 38 b and the dummyelectrodes 39 have the polygonal shapes having odd-numbered corners 38 aand 39 a in the plan view, the number of respective sides 38 c of eachhole 38 b which are parallel to the outer periphery P₁ of the pixel P isat most one.

Likewise, the number of respective sides 39 c of each dummy electrode 39which are parallel to the outer periphery P₁ of the pixel P is at mostone. For that reason, in the touch panel 42 and the liquid crystaldisplay device 1 according to this embodiment, the generation of moiréis suppressed as compared with the touch panel and the liquid crystaldisplay device with no provision of this configuration. As a result, theprevention of the visibility of the image displayed rough touch panel 42from being deteriorated can be realized.

FIG. 7 is a partially enlarged view illustrating still anothermodification of the touch panel 42 according to this embodiment in thesame viewing field as that in FIG. 4. As illustrated in FIG. 7, theholes 38 b and the dummy electrodes 39 may be shaped into octagonshaving eight corners 38 a and 39 a, respectively.

FIG. 8 is a partially enlarged view illustrating yet anothermodification of the touch panel 42 according to this embodiment the sameviewing field as that in FIG. 4. The holes 38 b and the dummy electrodes39 illustrated in FIG. 8 are shaped into dodecagons having 12 corners 38a and 39 a, respectively. If the number of corners 38 a and 39 a is thusfive or more, the number is not limited to the above example, and mayincrease more.

FIG. 9 is a partially enlarged view illustrating a further modificationof the touch panel 42 according to this embodiment in the same viewingfield as that in FIG. 4. The holes 38 b and the dummy electrodes 39 inFIG. 9 are each viewed as a circle in the plan view by increasing thenumber of corners 38 a and 39 a (for example, increasing the number ofcorners 38 a and 39 a to 20 or more). In the touch panel 42 and theliquid crystal display device according to this embodiment, with theprovision of the above configuration, portions in which the respectivesides 38 c of the holes 38 b and the outer periphery P₁ of the pixels P,and the respective sides 39 c of the dummy electrodes 39 and the outerperiphery P₁ of the pixels P are lined up in parallel to each other canbe minimized as compared with the touch panel or the liquid crystaldisplay device with no provision of the above configuration. For thatreason, the patterns of the detection electrodes 38 and the dummyelectrodes 39 can be viewed, and the generation of moiré can besuppressed. The plural holes 38 b of the detection electrodes 38 and theplural dummy electrodes 39 have only to be each shaped into the polygonhaving five or more corners in the plan view, and the number of cornersmay be different between the holes 38 b of the detection electrodes 38and the dummy electrodes 39. Also, in this case, the shapes S may bearranged and formed so that array pitches of the holes 38 b and thedummy electrodes 39 are maintained.

The array of the plural holes 38 b of the detection electrodes 38, andthe plural dummy electrodes 39 has been described above. The holes 38 band the dummy electrodes 39 may be arrayed except for in the zigzagarray. FIG. 10 is a partially enlarged view illustrating a still furthermodification of the touch panel 42 according to this embodiment in thesame viewing field as that in FIG. 4. As illustrated in FIG. 10, theholes 38 b and the dummy electrodes 39 may not be arrayed in the closestmanner.

Subsequently, a configuration of the touch panel 42 in the non-displayarea E will be described in detail. FIG. 11 is a partially enlarged viewof an area XI the touch panel 42 illustrated in FIG. 1, and FIG. 12 is apartially enlarged view of an area XII in the touch panel 42 illustratedin FIG. 1.

In the non-display area E, shield electrode 47 connected to the shieldterminal 41 is formed to extend in the direction Y. The shield electrode47 is an electrode configured to include a first area 48 which is anarea of the display area D side, and a second area 49 which is an areaoutside of the first area 48. The first area 48 is formed along aboundary F between the display area D and the non-display area E. Also,the first area 48 is formed over the overall area corresponding to thenon-display area E.

In the first area 48, as with the detection electrodes 38, holes 48 bhaving the same shape as that of the holes 38 b in the plan view areregularly formed. With this configuration, the first area 48 has thesame shape as that of the detection electrodes 38 in the plan view.

In the touch panel 42 and the liquid crystal display device 1 accordingto this embodiment, the shield electrode 47 (the first area 48) havingthe plural holes 48 b are formed along the boundary F in an areacorresponding to the non-display area E of the touch panel 42. As aresult, a shading difference within the non-display area E when thenon-display area is viewed from the outside of the touch panel 42 can besuppressed.

The embodiments of the present invention have been described above, butthe present invention is not limited to the above-mentioned embodiments.For example, the configuration described in the above-mentionedembodiments may be replaced with a substantially identicalconfiguration, a configuration having the same function effect, or aconfiguration that can achieve the identical purpose.

For example, in this embodiment, the touch panel 42 of the presentinvention is applied to the liquid crystal display device 1 of thein-cell system using the counter electrodes to which a voltage common tothe plural pixels adjacent to each other in the direction X is appliedas the scanning electrodes 30. Alternatively, the touch panel 42 of thepresent invention is not limited to the in-cell system, but can beapplied to an on-cell system in which both of the scanning electrodes 30and the detection electrodes 38 are formed over the second substrate 12,or a system in which a substrate on which the scanning electrodes andthe detection electrodes are formed is put on the display device. Also,the touch panel 42 of the present invention may be applied to thedisplay device (for example, an organic EL (electro luminescence)display device) other than the liquid crystal display device 1.

While there have been described what are at present considered to becertain embodiments of the invention, it will be understood that variousmodifications may be made thereto, and it is intended that the appendedclaims cover all such modifications as fall within the true spirit andscope of the invention.

What is claimed is:
 1. A display device comprising: a display panel; atouch panel including a plurality of scanning electrodes and a pluralityof detection electrodes that are formed to intersect with the pluralityof scanning electrodes, a plurality of holes that are arrayed apart fromeach other on each of the plurality of detection electrodes, and shapedinto polygons each shaped to have five or more corners in a plan view;and a plurality of dummy electrodes that are formed between therespective adjacent detection electrodes, made of the same material asthat of the detection electrode, and are arrayed apart from each other,wherein a surface shape of the plurality of dummy electrodes have thesame polygonal shape as that of the holes of the detection electrode. 2.The display device according to claim 1, wherein the plurality of holesshaped into the polygons and arrayed on the detection electrodes, andthe plurality of dummy electrodes form a uniform contiguous array. 3.The display device according to claim 1, wherein the planar view shapeof the polygons is viewed as a circle by increasing the number ofcorners.
 4. The display device according to claim 1, wherein in adetection electrode formation area in which the detection electrodes areformed, a ratio of an area of the plurality of holes to an area of thedetection electrodes is equal to or larger than ⅔ and equal to orsmaller than 3/2.
 5. The display device according to claim 1, whereindistances between centers of the respective adjacent polygons are equalto each other.
 6. The display device according to claim 1, furthercomprising a shield electrode which is an electrode in which theplurality of holes shaped into the polygons are formed outside of adisplay area in which the detection electrodes are formed.
 7. Thedisplay device according to claim 1, wherein the plurality of detectionelectrodes are formed on the display panel.
 8. A display devicecomprising: a display panel; a touch panel including a plurality ofscanning electrodes and a plurality of detection electrodes that areformed to intersect with the plurality of scanning electrodes; aplurality of holes shaped that are arrayed apart from each other on eachof the plurality of detection electrodes, and shaped into polygons eachshaped to have five or more corners in a plan view; and a plurality ofdummy electrodes that are formed between the respective adjacentdetection electrodes, made of the same material as that of the detectionelectrode, and are arrayed apart from each other, wherein a surfaceshape of the plurality of dummy electrodes are shaped into polygons eachhaving five or more corners in a plan view.
 9. The display deviceaccording to claim 8, wherein an area of the hole shaped on thedetection electrodes is same as that of the dummy electrode.
 10. Thedisplay device according to claim 8, wherein the plurality of holesshaped into the polygons and arrayed on the detection electrodes, andthe plurality of dummy electrodes form a uniform contiguous array. 11.The display device according to claim 8, wherein in a detectionelectrode formation area in which the detection electrodes are formed, aratio of an area of the plurality of holes to an area of the detectionelectrodes is equal to or larger than ⅔ and equal to or smaller than3/2.
 12. The display device according to claim 8, wherein distancesbetween centers of the respective adjacent polygons are equal to eachother.
 13. The display device according to claim 8, further comprising ashield electrode which is an electrode in which the plurality of holesshaped into the polygons are formed outside of a display area in whichthe detection electrodes are formed.
 14. The display device according toclaim 8, wherein the plurality of detection electrodes are formed on thedisplay panel.